JP2015189373A - Electric brake device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric brake device capable of performing control according to an intention of a driver when a system is restored after system off even when the system is turned off in the middle of actuation (holding or release) control of a brake mechanism.SOLUTION: A parking brake control device 19 performs holding (application) or release of a disk brake 31 by driving an electric actuator 43 according to an actuation request signal based on an operation of a parking brake switch 18, etc. In this case, the parking brake control device 19 restarts uncompleted control from the middle in the case that a new actuation request signal is generated when a system is restored, and it is detected that control of the holding or release is interrupted as uncompleted after the system is turned off in the middle of the control of the holding or release of the disk brake 31.

Description

  The present invention relates to an electric brake device that applies a braking force to a vehicle such as an automobile.

  As a brake device mounted on a vehicle such as an automobile, for example, a brake device with an electric parking brake function (electric brake device) that operates based on driving of an electric actuator is known (Patent Document 1).

  In the prior art according to Patent Document 1, when the parking brake is in operation, that is, in the middle of holding (applying) or in the middle of releasing (releasing), the system stops and the control is incomplete. When is restored, the incomplete control is resumed.

JP 2007-216896 A

  In the prior art disclosed in Patent Literature 1, for example, when the system stops during the control of holding (applying) the parking brake, and then the system returns, the holding of the parking brake resumes. In this case, for example, when the vehicle is traveling, there is a possibility that a braking force unintended by the driver (driver) may be applied.

  The present invention has been made in view of the above-described problems of the prior art, and the object of the present invention is when the system returns after the system is turned off even during the control of the operation (holding or releasing) of the brake mechanism. An object of the present invention is to provide an electric brake device capable of performing control according to the driver's intention.

  In order to solve the above-described problems, an electric brake device according to the present invention includes an electric actuator that operates a brake mechanism in response to an operation request signal, and an operation of the electric actuator by a power source provided in a vehicle to control the brake mechanism. Actuator control means for controlling holding and release of the brake, and the actuator control means returns to the system after the system is turned off during the holding or releasing control of the brake mechanism, and does not perform the holding or releasing control. When it is detected that the operation has been interrupted while being completed, if a new operation request signal is generated, the incomplete control is restarted from the middle.

  According to the electric brake device of the present invention, even if the system is turned off in the middle of the control (holding or releasing) of the brake mechanism, the control according to the driver's intention can be performed when the system is subsequently restored. it can.

1 is a conceptual diagram of a vehicle on which an electric brake device according to a first embodiment is mounted. It is a block diagram which shows the parking brake control apparatus in FIG. It is a longitudinal cross-sectional view which expands and shows the disc brake with an electric parking brake function provided in the rear-wheel side in FIG. It is a flowchart which shows the control processing by a parking brake control apparatus. It is explanatory drawing which shows the time change of operation | movement of an electric actuator, and a control state. It is a flowchart which shows the control processing of the parking brake control apparatus by 2nd Embodiment. It is explanatory drawing which shows the time change of operation | movement of an electric actuator, and a control state.

  Hereinafter, the case where the brake device according to the embodiment is mounted on a four-wheel vehicle will be described as an example, and will be described in detail with reference to the accompanying drawings.

  1 to 5 show a first embodiment. In FIG. 1, there are four wheels, for example, left and right front wheels 2 (FL, FR) and left and right rear wheels 3 (RL,) on the lower side (road surface side) of the vehicle body 1 constituting the vehicle body. RR). Each front wheel 2 and each rear wheel 3 is provided with a disk rotor 4 as a rotating member (disk) that rotates together with each wheel (each front wheel 2 and each rear wheel 3). That is, each front wheel 2 is sandwiched by each disc rotor 4 by a hydraulic disc brake 5, and each rear wheel 3 is sandwiched by each disc rotor 4 by a hydraulic disc brake 31 with an electric parking brake function, which will be described later. The As a result, a braking force is applied to each wheel (each front wheel 2 and each rear wheel 3).

  A brake pedal 6 is provided on the front board side of the vehicle body 1. The brake pedal 6 is depressed by a driver (driver) when the vehicle is braked. The brake pedal 6 is provided with a brake pedal operation detection sensor (brake sensor) 6A such as a pedal switch and a pedal stroke sensor. The brake pedal operation detection sensor 6A detects whether or not the brake pedal 6 is depressed or the operation amount thereof, and outputs a detection signal to the hydraulic pressure supply controller 13 described later. The detection signal of the brake pedal operation detection sensor 6A may be configured to be output to a parking brake control device 19 described later.

  The depression operation of the brake pedal 6 is transmitted to the master cylinder 8 via the booster 7. The booster 7 is composed of a negative pressure booster, an electric booster, or the like provided between the brake pedal 6 and the master cylinder 8. The booster 7 increases the pedaling force and transmits it to the master cylinder 8 when the brake pedal 6 is depressed. At this time, the master cylinder 8 generates hydraulic pressure with the brake fluid supplied from the master reservoir 9. The master reservoir 9 constitutes a hydraulic fluid tank that contains brake fluid. The mechanism for generating the hydraulic pressure by the brake pedal 6 is not limited to the above, and a mechanism for generating the hydraulic pressure in response to the operation of the brake pedal 6 such as a brake-by-wire mechanism may be used.

  The hydraulic pressure generated in the master cylinder 8 is sent to a hydraulic pressure supply device 11 (hereinafter referred to as ESC 11) via, for example, a pair of cylinder side hydraulic pipes 10A and 10B. The ESC 11 distributes and supplies the hydraulic pressure from the master cylinder 8 to the disc brakes 5 and 31 via the brake side piping portions 12A, 12B, 12C, and 12D. As a result, a braking force is applied to each wheel (each front wheel 2 and each rear wheel 3) as described above.

  The ESC 11 is disposed between the disc brakes 5, 31 and the master cylinder 8. The ESC 11 has a hydraulic pressure supply controller 13 (hereinafter referred to as a control unit 13) that controls the operation thereof. The control unit 13 increases the brake fluid pressure of each of the disc brakes 5, 31 by supplying the brake fluid to each of the disc brakes 5, 31 from the brake side piping parts 12 </ b> A to 12 </ b> D by controlling the drive of the ESC 11. , Depressurize or hold control. Thereby, for example, brake control such as boost control, braking force distribution control, brake assist control, anti-skid control, traction control, vehicle stabilization control including skid prevention, and slope start assist control is executed.

  The control unit 13 is configured by a microcomputer or the like, and power from the battery 14 is supplied through the power line 15. The control unit 13 is connected to a vehicle data bus 16 and the like as shown in FIG. In addition, you may use a well-known ABS unit instead of ESC11. Furthermore, it is good also as a structure which does not provide ESC11 (it abbreviate | omits) and connects to the brake side piping parts 12A-12D directly from the master cylinder 8. FIG.

  The vehicle data bus 16 includes a CAN as a serial communication unit mounted on the vehicle body 1, and is connected to a large number of electronic devices mounted on the vehicle, the control unit 13, a parking brake control device 19 described later, and the like. It performs multiplex communication for in-vehicle use. In this case, vehicle information sent to the vehicle data bus (CAN) 16 includes, for example, a steering angle sensor, an accelerator sensor (accelerator pedal operation detection sensor), a throttle sensor, an engine rotation sensor, and a brake sensor (brake pedal operation detection sensor 6A). , Wheel speed sensor, vehicle speed sensor, tilt sensor, G sensor (acceleration sensor), stereo camera, millimeter wave radar, seat belt sensor, information such as detection signal from transmission sensor, etc., and detection from pressure sensor 17 etc. Signal (information).

  The pressure sensor 17 is provided in each of the brake side piping sections 12A, 12B, 12C, and 12D, and each caliper 34 (cylinder) described later corresponding to the pressure (hydraulic pressure) in each pipeline, in other words, the pressure in the pipeline. The hydraulic pressure (wheel cylinder hydraulic pressure) in the part 36) is individually detected. One or two pressure sensors 17 may be provided. For example, the pressure sensor 17 is provided only in the cylinder side hydraulic pipes 10A and 10B between the master cylinder 8 and the ESC 11 (detects the master cylinder hydraulic pressure). Also good.

  The vehicle body 1 is provided with a parking brake switch 18 located in the vicinity of a driver's seat (not shown), and the parking brake switch 18 is operated by a driver. The parking brake switch 18 transmits a parking brake operation request (holding request / release request) from the driver to a parking brake control device 19 described later.

  When the parking brake switch 18 is operated to the braking side (parking brake ON side), that is, when there is a holding request (driving request) from the driver, the rear wheel 3 is connected via the parking brake control device 19 described later. Electric power for rotating an electric actuator 43 (described later) to the braking side is supplied to the disc brake 31 on the side. Thereby, the disc brake 31 on the rear wheel 3 side is in a state where a braking force as a parking brake is applied, that is, in a holding state (applied state). In this specification, applying the parking brake, that is, applying the braking force as the parking brake will be described using the word “hold”. This applies a predetermined pressing force (thrust) to a brake pad 33 to be described later by driving the electric actuator 43, and the positions of the piston 39 and the brake pad 33 at that time are determined as a pressing member holding mechanism (rotational linear motion conversion mechanism 40). This term is used because it is held by.

  On the other hand, when the parking brake switch 18 is operated to the brake release side (parking brake OFF side), that is, when there is a release request from the driver, the disc brake 31 is electrically operated via the parking brake control device 19. Electric power is supplied to rotate the actuator 43 in the direction opposite to the braking side. As a result, the disc brake 31 on the rear wheel 3 side is in a state in which the application of the braking force as the parking brake is released, that is, in the released state (release state).

  The parking brake is used when the vehicle is stopped (for example, when a state of less than 4 km / h has continued for a predetermined time during deceleration for a predetermined time during traveling) or when the engine is stopped (engine stalled). Based on the automatic holding request (automatic holding request) by the parking brake holding judgment logic in the parking brake control device 19, such as when operating (parking), when the door is opened, when the seat belt is released, etc. In addition, the braking force can be automatically applied (held). The parking brake is operated when, for example, the vehicle has traveled (for example, when a state of 5 km / h or more has continued for a predetermined period of time since the vehicle stopped) or when the accelerator pedal is operated. When the shift lever is operated other than P, N (neutral), etc., automatically based on the automatic release request (automatic release request) by the parking brake release determination logic in the parking brake control device 19 The braking force can be released.

  The parking brake control device 19 constitutes an electric brake system (electric brake device) together with a pair of left and right disc brakes 31 described later. As shown in FIG. 2, the parking brake control device 19 has an arithmetic circuit (CPU) 20 configured by a microcomputer or the like, and power from the battery 14 is supplied to the parking brake control device 19 through the power supply line 15. Is done.

  The parking brake control device 19 constitutes an actuator control means (controller, control unit), and controls an electric actuator 43 of a disc brake 31 described later so that the vehicle can be parked and stopped (running if necessary). A braking force (parking brake, auxiliary brake) is generated. That is, the parking brake control device 19 operates (holds / releases) the disc brake 31 as a parking brake (auxiliary brake if necessary). In other words, the parking brake control device 19 controls the holding and releasing of the disc brake 31 by controlling the operation of the electric actuator 43 by the power source (battery 14 in the first embodiment) provided in the vehicle. It is.

  Here, the parking brake control device 19 is based on a signal (ON / OFF signal) output from the parking brake switch 18 when the driver of the vehicle operates the parking brake switch 18. And the disc brake 31 is held (applied) or released (released). In addition to the signal from the parking brake switch 18, the parking brake control device 19 drives the electric actuator 43 and holds or releases the disc brake 31 based on the above-described determination logic for holding and releasing the parking brake. .

  In this way, the parking brake control device 19 includes an “operation request signal” including a signal of the parking brake switch 18 and a signal based on the above-described determination logic of holding / release of the parking brake, that is, operation of the parking brake (hold / release When the "operation request signal" is requested, the disc brake 31 is held or released according to the request. At this time, in the disc brake 31, the piston 39 and the brake pad 33 are held or released by the pressing member holding mechanism (rotation linear motion conversion mechanism 40) based on the drive of the electric actuator 43. Therefore, the “operation request signal” is a signal for performing the holding operation or the release operation of the piston 39 and the brake pad 33 by the pressing member holding mechanism (rotational linear motion conversion mechanism 40).

  As shown in FIGS. 1 to 3, the parking brake control device 19 has an input side connected to the parking brake switch 18 and the like, and an output side connected to the electric actuator 43 and the like of the disc brake 31. More specifically, as shown in FIG. 2, the arithmetic circuit (CPU) 20 of the parking brake control device 19 includes a parking brake switch 18, a vehicle data bus (in addition to a storage unit (memory) 21 described later). CAN) 16, a voltage sensor unit 22, a motor drive circuit 23, a current sensor unit 24, and the like, which will be described later, are connected. From the vehicle data bus 16, various state quantities of the vehicle necessary for the control (operation) of the parking brake, that is, the various vehicle information described above can be acquired.

  The vehicle information acquired from the vehicle data bus 16 is a parking brake control of sensors (for example, an accelerator sensor, a throttle sensor, an engine rotation sensor, a brake sensor, a wheel speed sensor, a vehicle speed sensor, and a G sensor) that detect the information. It is good also as a structure acquired by connecting directly to the apparatus 19 (the arithmetic circuit 20). The arithmetic circuit 20 of the parking brake control device 19 is configured to receive an operation request signal from the parking brake switch 18 and another control device (for example, the control unit 13) connected to the vehicle data bus 16. be able to.

  In this case, for example, the parking brake holding / releasing determination based on the above-described determination logic may be performed by another control device, for example, the control unit 13, instead of the parking brake control device 19. That is, the control content of the parking brake control device 19 can be integrated into the control unit 13.

  The parking brake control device 19 has a storage unit (memory) 21 (see FIG. 2) composed of, for example, a flash memory, ROM, RAM, EEPROM, etc., and the storage unit 21 holds and releases the parking brake described above. A determination logic program, a processing program shown in FIG. 4 to be described later, that is, whether or not the disc brake 31 can be held (braking applied) and released (braking released) by the electric actuator 43, and held or released according to the determination. A processing program to be executed is stored.

  Further, the storage unit 21 of the parking brake control device 19 stores the control state of the disc brake 31 (“holding”, “holding”, “released”, “released”, “unknown”) in an updatable manner. The That is, the storage unit 21 stores “holding”, “holding”, “release” corresponding to the state of the parking brake by the electric actuator 43, in other words, the state of the piston 39 by the rotation / linear motion conversion mechanism 40 described later. One of the states “Unlocking” and “Unknown” is stored every time the state (status) is changed. In this case, in the arithmetic circuit 20 of the parking brake control device 19, the control state of the disc brake 31 (piston 39) is any of “holding”, “holding”, “released”, “released”, and “unknown”. It is determined whether or not there is, and the determination result is stored in the storage unit 21 at any time or at the timing of the activation process (data is rewritten).

  Specifically, in the arithmetic circuit 20, when the holding of the piston 39 by the rotation / linear motion converting mechanism 40 is completed, the holding flag is raised, and when the releasing of the piston 39 is completed, the releasing flag is raised. The storage unit 21 stores the state of the piston 39 by the rotation / linear motion conversion mechanism 40 as “hold (fastened)” when the hold flag is raised, and as “release” when the release flag is raised. . In addition, the period from when the driving of the electric actuator 43 is started until the holding flag or the release flag rises is stored as “holding (fastening)” or “released”.

  That is, the control state of the disc brake 31 becomes “holding (engaged)” when the parking brake holding (engaged) is started, and “holding (when the holding flag is raised)” is completed when the holding control is completed. Conclusion) ”. On the other hand, when the release of the parking brake is started, it becomes “released” and becomes “released” when the release control is completed (when the release flag is raised). Further, when it is not possible to determine “holding”, “release”, “holding”, or “released”, such as when control state storage (writing) in the storage unit 21 has failed, the arithmetic circuit 20 is determined as “unknown”.

  The control state of the disc brake 31 (the state of the rotation / linear motion conversion mechanism 40, the state of the piston 39) stored in the storage unit 21 is a non-volatile storage device (memory) that can maintain the memory even when power is not supplied, For example, it is stored in an EEPROM. This is because the power supply to the parking brake control device 19 is temporarily cut off, for example, when the power of the power supply line 15 becomes unstable and the power is temporarily reduced. This is because the system can be used immediately even when the system is turned off (system down) and then the power is restored and the system is restored (restarted). In this case, if the control state is “holding” when the system returns, the arithmetic circuit 20 can determine that the parking brake holding control is interrupted (finished halfway), and the control state is “ If it is “under release”, it can be determined that the parking brake release control is interrupted (finished halfway).

  In the first embodiment, the parking brake control device 19 is separated from the control unit 13 of the ESC 11, but the parking brake control device 19 may be configured integrally with the control unit 13. The parking brake control device 19 controls the two disc brakes 31 on the left and right, but may be provided for each of the left and right disc brakes 31. In this case, the parking brake The control device 19 can also be provided integrally with the disc brake 31.

  As shown in FIG. 2, the parking brake control device 19 includes a voltage sensor unit 22 that detects a voltage from the power supply line 15, and left and right motor drive circuits 23 that drive left and right electric actuators 43 and 43, respectively. , 23, left and right electric current actuators 43, 43, and left and right current sensor sections 24, 24 for detecting the respective motor currents. The voltage sensor unit 22, the motor drive circuit 23, and the current sensor unit 24 are connected to the arithmetic circuit 20, respectively.

  Thereby, the arithmetic circuit 20 of the parking brake control device 19 drives the electric actuator 43 based on the motor current value of the electric actuator 43 when holding (applying) or releasing (release) the parking brake, for example. Can be stopped. In this case, when holding the parking brake, the arithmetic circuit 20, for example, when the motor current value reaches a holding threshold value (current value corresponding to the thrust to be generated at that time), the rotation / linear motion conversion mechanism 40. It is determined that the state of the piston 39 has become the holding state, and the driving of the electric actuator 43 is stopped. On the other hand, when the parking brake is released, the arithmetic circuit 20 determines that, for example, when the motor current value reaches a preset release threshold, the state of the piston 39 by the rotation / linear motion conversion mechanism 40 is released. Determination is made, and driving of the electric actuator 43 is stopped.

  Here, in the first embodiment, the parking brake control device 19 returns to the system after the system is turned off during the holding or releasing control of the disc brake 31, and interrupts the holding or releasing control without being completed. When a new operation request signal (holding operation request signal, release operation request signal) is generated when it is detected that the operation has been performed, uncompleted control is resumed from the middle. . That is, as shown in FIG. 4 to be described later, the parking brake control device 19 may stop the parking brake holding control or release control without completing the operation, in other words, the control state of the disc brake 31 is “ Even if the operation is interrupted (for example, when the system is turned off) by “holding” or “released”, the parking brake switch 18 or the above-mentioned control is not resumed after that (for example, when the system is started). The control according to the new operation request signal is resumed on the condition that a new operation request signal is generated by the determination brake brake holding / release logic.

  In this case, in addition to the case where the new operation request signal is the same as the operation request signal for the incomplete control, the parking brake control device 19 performs the operation request for the control in which the new operation request signal is incomplete. Even when it differs from the signal, the control according to the new operation request signal is resumed. In other words, the parking brake control device 19 uses the electric actuator when a new operation request signal is a holding request regardless of whether the control state of the disc brake 31 is interrupted due to “holding” or interrupted due to “releasing”. 43 is driven to the holding side (apply side), and when the new operation request signal is a release request, the electric actuator 43 is driven to the release side (release side).

  Further, when the vehicle is running, the parking brake control device 19 detects that the holding or releasing control has been interrupted without being completed, and a new operation request signal is generated when the parking brake is held. In the case of a request signal, it is configured to prohibit resumption of incomplete control from the middle. That is, when it is determined that the vehicle is running, the parking brake control device 19 generates a new operation request signal regardless of whether the control state of the disc brake 31 is “holding” or “releasing”. In the case of a holding request (auxiliary brake request, emergency stop request), it is prohibited to drive the electric actuator 43 to the holding side (apply side). The control process of FIG. 4 performed by the parking brake control device 19 will be described in detail later.

  Next, the structure of the disc brakes 31 and 31 with the electric parking brake function provided on the left and right rear wheels 3 and 3 will be described with reference to FIG. FIG. 3 shows only one of the left and right disc brakes 31 and 31 provided corresponding to the left and right rear wheels 3 and 3, respectively.

  A pair of disc brakes 31 provided respectively on the left and right sides of the vehicle as a brake mechanism are configured as hydraulic disc brakes provided with an electric parking brake function. The disc brake 31 constitutes an electric brake system (electric brake device) together with the parking brake control device 19. The disc brake 31 includes an attachment member 32 attached to a non-rotating portion on the rear wheel 3 side of the vehicle, an inner side and outer side brake pad 33 as a friction member, and a caliper 34 provided with an electric actuator 43 described later. It is comprised including. In this case, the disc brake 31 propels a piston 39, which will be described later, that presses the brake pad 33 by hydraulic pressure, and electrically drives the disc brake 31 in accordance with a braking request signal based on the parking brake switch 18 or the above-described parking brake holding determination logic. The actuator 43 propels the piston 39 to press the brake pad 33 against the disc rotor 4 so that the pressing force of the piston 39, that is, the pressing force of the brake pad 33 can be held.

  The mounting member 32 includes a pair of arm portions (not shown) that extend in the axial direction of the disk rotor 4 (that is, the disk axial direction) so as to straddle the outer periphery of the disk rotor 4, and are separated from each other in the disk circumferential direction. A thick-walled support portion 32A that is fixed to a non-rotating portion of the vehicle at a position on the inner side of the disk rotor 4 and is connected to the base end side of the disk rotor 4; And a reinforcing beam 32B for connecting the distal end sides of the arm portions to each other.

  The inner side and outer side brake pads 33 constitute a friction member, and are arranged so as to be able to contact both surfaces of the disc rotor 4 and supported by the respective arm portions of the mounting member 32 so as to be movable in the disc axial direction. ing. The inner and outer brake pads 33 are pressed against both sides of the disc rotor 4 by calipers 34 (caliper main body 35 and piston 39) described later.

  A caliper 34 is disposed on the mounting member 32 so as to straddle the outer peripheral side of the disk rotor 4. The caliper 34 is generally constituted by a caliper body 35 supported so as to be movable along the axial direction of the disk rotor 4 with respect to the respective arm portions of the mounting member 32, and a piston 39 provided in the caliper body 35. Has been. The caliper 34 is provided with a rotation / linear motion conversion mechanism 40 and an electric actuator 43 which will be described later.

  The caliper body 35 includes a cylinder part 36, a bridge part 37, and a claw part 38. The cylinder portion 36 is formed in a bottomed cylindrical shape in which one side in the axial direction is closed as a partition wall portion 36A and the other side facing the disk rotor 4 is an open end. The bridge portion 37 is formed to extend from the cylinder portion 36 in the disc axial direction so as to straddle the outer peripheral side of the disc rotor 4. The claw portion 38 is disposed so as to extend on the opposite side of the cylinder portion 36 with the bridge portion 37 interposed therebetween.

  The cylinder portion 36 of the caliper main body 35 is supplied with hydraulic pressure accompanying the depression operation of the brake pedal 6 or the like via the brake side piping portion 12C or 12D shown in FIG. The cylinder portion 36 is integrally formed with a partition wall portion 36 </ b> A so as to be positioned between the cylinder portion 36 and an electric actuator 43 described later. An output shaft 43B of the electric actuator 43 is rotatably inserted on the inner peripheral side of the partition wall portion 36A. In the cylinder portion 36 of the caliper main body 35, a piston 39 as a pressing member, a rotation / linear motion conversion mechanism 40 described later, and the like are provided.

  In the first embodiment, the rotation / linear motion conversion mechanism 40 is configured to be accommodated in the piston 39, but the piston 39 is propelled by the rotation / linear motion conversion mechanism 40. If so, the rotation / linear motion conversion mechanism 40 is not necessarily accommodated in the piston 39.

  Here, one side of the piston 39 in the axial direction which is the opening side is inserted into the cylinder portion 36, and the other side in the axial direction facing the brake pad 33 on the inner side is closed as a lid portion 39A. Further, a rotation / linear motion conversion mechanism 40 is accommodated in the piston 39 inside the cylinder portion 36, and the piston 39 is propelled in the axial direction of the cylinder portion 36 by the rotation / linear motion conversion mechanism 40. It has become. The rotation / linear motion converting mechanism 40 constitutes a pressing member holding mechanism. In addition to the addition of the hydraulic pressure into the cylinder portion 36, the piston 39 of the caliper 34 is propelled by an external force, that is, the electric actuator 43, and propulsion is performed. The piston 39 and the brake pad 33 are held. Since the left and right disc brakes 31 are provided corresponding to the left and right rear wheels 3, the rotation / linear motion conversion mechanism 40 and the electric actuator 43 are also provided on the left and right sides of the vehicle, respectively.

  The rotation / linear motion conversion mechanism 40 includes a screw member 41 made of a rod-like body in which a male screw such as a trapezoidal screw is formed, and a linear motion member 42 serving as a propulsion member in which a female screw hole made of a trapezoidal screw is formed on the inner peripheral side. It is configured. That is, the screw member 41 screwed to the inner peripheral side of the linear motion member 42 constitutes a screw mechanism that converts a rotational motion by an electric actuator 43 described later into a linear motion of the linear motion member 42. In this case, the female screw of the linear motion member 42 and the male screw of the screw member 41 are highly irreversible screws, and in the first embodiment, a trapezoidal screw is used to form a pressing member holding mechanism. Yes. This pressing member holding mechanism (rotation / linear motion conversion mechanism 40) causes the friction of the linear motion conversion mechanism 40 inside the rotation / linear motion conversion mechanism 40 at an arbitrary position even when power supply to the electric actuator 43 is stopped. It is held by force (holding force). The pressing member holding mechanism only needs to be able to hold the piston 39 at a position propelled by the electric actuator 43. For example, the pressing member holding mechanism may be a normal triangular cross-section screw or a worm gear having a large irreversibility other than a trapezoidal screw.

  The screw member 41 that is screwed to the inner peripheral side of the linear motion member 42 is provided with a flange portion 41A that is a large-diameter flange on one side in the axial direction, and the other side in the axial direction is a lid of the piston 39. It extends toward the portion 39A side. The screw member 41 is integrally connected to an output shaft 43B of an electric actuator 43 described later on the flange portion 41A side. Further, on the outer peripheral side of the linear motion member 42, an engagement protrusion 42A is provided that prevents the linear motion member 42 from rotating relative to the piston 39 (relative rotation is restricted) and allows relative movement in the axial direction.

  An electric actuator 43 as a parking brake actuator (electric mechanism) is provided in the casing 43A. The casing 43A is fixed to the cylinder portion 36 of the caliper body 35 at a position outside the partition wall portion 36A. The electric actuator 43 operates (holds / releases) the disc brake 31 in accordance with the above-described operation request signal (holding operation request signal, release operation request signal). An electric motor and a speed reducer (none of which is shown) for increasing the torque of the electric motor are included. The speed reducer has an output shaft 43B that outputs the increased rotational torque. The output shaft 43B extends through the partition wall portion 36A of the cylinder portion 36 in the axial direction, and is connected to rotate integrally with the flange portion 41A side of the screw member 41 within the cylinder portion 36.

  The connecting means for connecting the output shaft 43B and the screw member 41 can be configured to be movable in the axial direction, for example, but not to rotate in the rotational direction. In this case, a known technique such as spline fitting or fitting with a polygonal column (non-circular fitting) is used. As the speed reducer, for example, a planetary gear speed reducer or a worm gear speed reducer may be used. When a known speed reducer that does not have reverse operation (irreversible) such as a worm gear speed reducer is used, the rotation / linear motion conversion mechanism 40 is a known reversible mechanism such as a ball screw or a ball ramp mechanism. Can be used. In this case, for example, the pressing member holding mechanism can be configured by a reversible rotation / linear motion conversion mechanism and an irreversible speed reducer.

  Here, when the parking brake switch 18 shown in FIGS. 1 to 3 is operated to the braking side by the driver, the parking brake control device 19 supplies power to the electric actuator 43 (the electric motor thereof) and The output shaft 43B is rotated. For this reason, the screw member 41 of the rotation / linear motion converting mechanism 40 rotates integrally with the output shaft 43B in, for example, one direction, and propels (drives) the piston 39 toward the disk rotor 4 via the linear motion member 42. As a result, the disc brake 31 is in a state in which the disc rotor 4 is sandwiched between the inner and outer brake pads 33 and a braking force is applied as an electric parking brake, that is, a holding state (applied state).

  On the other hand, when the parking brake switch 18 is operated to the brake release side, the parking brake control device 19 rotates the screw member 41 of the rotation / linear motion conversion mechanism 40 in the other direction (reverse direction) by the electric actuator 43. As a result, the linear motion member 42 is driven in a direction away (separated) from the disc rotor 4 via the rotary / linear motion conversion mechanism 40, and the disc brake 31 is released from the application of the braking force as a parking brake, that is, , The release state (release state).

  In this case, in the rotation / linear motion converting mechanism 40, when the screw member 41 is rotated relative to the linear motion member 42, the rotation of the linear motion member 42 in the piston 39 is restricted. Is relatively moved in the axial direction according to the rotation angle of the screw member 41. Thereby, the rotation / linear motion converting mechanism 40 converts the rotational motion into a linear motion, and the piston 39 is driven by the linear motion member 42. At the same time, the rotation / linear motion conversion mechanism 40 holds the linear motion member 42 at an arbitrary position by a frictional force with the screw member 41, so that the piston 39 and the brake pad 33 are propelled by the electric actuator 43. Hold on.

  A thrust bearing 44 is provided between the partition wall portion 36 </ b> A of the cylinder portion 36 and the flange portion 41 </ b> A of the screw member 41. The thrust bearing 44 receives the thrust load from the screw member 41 together with the partition wall portion 36A, and smoothes the rotation of the screw member 41 with respect to the partition wall portion 36A. In addition, a seal member 45 is provided between the partition wall portion 36A of the cylinder portion 36 and the output shaft 43B of the electric actuator 43. The seal member 45 causes the brake fluid in the cylinder portion 36 to leak to the electric actuator 43 side. It seals between the two so as to prevent it.

  A piston seal 46 as an elastic seal that seals between the cylinder portion 36 and the piston 39 and a dust boot 47 that prevents foreign matter from entering the cylinder portion 36 are provided on the opening end side of the cylinder portion 36. It has been. The dust boot 47 is configured by a flexible bellows-like seal member, and is attached between the opening end of the cylinder portion 36 and the outer periphery of the piston 39 on the lid portion 39A side.

  The disc brake 5 on the front wheel 2 side has substantially the same configuration except for the disc brake 31 on the rear wheel 3 side and the parking brake mechanism. That is, the disc brake 5 on the front wheel 2 side is not provided with the rotation / linear motion conversion mechanism 40 for operating (holding / releasing) the parking brake, the electric actuator 43 and the like, unlike the disc brake 31 on the rear wheel 3 side. . However, in other respects, the disc brake 5 on the front wheel 2 side is configured in substantially the same manner as the disc brake 31. In some cases, a disc brake 31 with an electric parking brake function may be provided on the front wheel 2 side instead of the disc brake 5.

  In the first embodiment, the hydraulic disc brake 31 having the caliper 34 provided with the electric actuator 43 has been described as an example. However, it is not limited to this, for example, an electric disc brake having an electric caliper, an electric drum brake having an electric drum that applies a braking force by an electric actuator, a disc brake having an electric drum type parking brake, and the like. If the brake mechanism can hold the pressing force after the friction member (pad, shoe) is pressed (promoted) against the rotating member (disk rotor, drum) by the electric actuator (electric motor), the configuration May not be the brake mechanism having the configuration of the above-described embodiment.

  The brake device for a four-wheeled vehicle according to the first embodiment has the above-described configuration. Next, the operation thereof will be described.

  When the driver of the vehicle depresses the brake pedal 6, the pedaling force is transmitted to the master cylinder 8 via the booster 7, and brake fluid pressure is generated by the master cylinder 8. The hydraulic pressure generated in the master cylinder 8 is distributed and supplied to the disc brakes 5 and 31 via the cylinder side hydraulic pipes 10A and 10B, the ESC 11, and the brake side pipes 12A, 12B, 12C and 12D, and left and right. Braking force is applied to the front wheel 2 and the left and right rear wheels 3 respectively.

  In this case, the disc brake 31 on the rear wheel 3 side will be described. The hydraulic pressure is supplied into the cylinder portion 36 of the caliper 34 via the brake side piping portions 12C and 12D, and the piston 39 is increased according to the increase in the hydraulic pressure in the cylinder portion 36. Is slidingly displaced toward the brake pad 33 on the inner side. As a result, the piston 39 presses the inner brake pad 33 against one side surface of the disk rotor 4, and the entire caliper 34 is against the arms of the mounting member 32 by the reaction force at this time. Sliding displacement to the side.

  As a result, the outer leg portion (claw portion 38) of the caliper 34 operates to press the brake pad 33 on the outer side against the disc rotor 4, and the disc rotor 4 is moved from both sides in the axial direction by the pair of brake pads 33. The braking force according to the hydraulic pressure application is generated. On the other hand, when the brake operation is released, the hydraulic pressure supply into the cylinder part 36 is released and stopped, so that the piston 39 is displaced so as to move backward into the cylinder part 36, and the inner side and outer side brakes are released. As the pad 33 moves away from the disc rotor 4, the vehicle is returned to the non-braking state.

  Next, when the driver of the vehicle operates the parking brake switch 18 to the braking side (ON), power is supplied from the parking brake control device 19 to the electric actuator 43 of the disc brake 31, and the output shaft 43B of the electric actuator 43 is Driven by rotation. The disc brake 31 with an electric parking brake function converts the rotation of the electric actuator 43 into linear motion via the screw member 41 and the linear motion member 42 of the rotation / linear motion conversion mechanism 40 and moves the linear motion member 42 in the axial direction. The piston 39 is propelled to push the pair of brake pads 33 against both sides of the disc rotor 4.

  At this time, the linear motion member 42 is held in a braking state by a frictional force (holding force) generated between the linearly acting member 42 and the screw member 41 using the pressing reaction force transmitted from the piston 39 as a vertical reaction force. The disc brake 31 is actuated (applied) as a parking brake. That is, even after the power supply to the electric actuator 43 is stopped, the linear motion member 42 (that is, the piston 39) can be held at the braking position by the female screw of the linear motion member 42 and the male screw of the screw member 41.

  On the other hand, when the driver operates the parking brake switch 18 to the brake release side (off), electric power is supplied from the parking brake control device 19 to the electric actuator 43 in the reverse direction of the motor, and the output shaft 43B of the electric actuator 43 is parked. It is rotated in the opposite direction to when the brake is applied (during application). At this time, the rotation / linear motion conversion mechanism 40 releases the holding of the braking force by the screw member 41 and the linear motion member 42 and moves the linear motion member 42 to the cylinder portion with a movement amount corresponding to the reverse rotation of the electric actuator 43. 36 is moved in the return direction to release the braking force of the parking brake (disc brake 31).

  By the way, during the parking brake holding (apply) control, for example, when the system is temporarily stopped (system off) due to a temporary decrease in power, etc., and the holding control is interrupted, the system then returns. For example, it is conceivable to resume the suspended holding control unconditionally. However, in this case, when the system returns, for example, if the vehicle is traveling, there is a risk that a braking force unintended by the driver (driver) may be applied. On the other hand, if the system is temporarily stopped during the parking brake release (release) control, and the release control is interrupted, when the system is subsequently restored, the interrupted release control is resumed unconditionally. Depending on the state of the vehicle at that time, there is a risk that the driver will unintentionally release the brake.

  On the other hand, in the first embodiment, the parking brake control device 19 determines that the parking brake holding or releasing control is interrupted without being completed, that is, the disc brake 31 (the electric actuator 43 thereof) is “ In the case of interruption (termination) in the control state of “holding” or “released”, it is not completed on condition that a new operation request signal is generated by the parking brake switch 18 or the above-described parking brake holding / release determination logic. The control according to the new operation request signal is resumed from the control state. Hereinafter, control processing (parking brake holding and releasing processing) performed by the arithmetic circuit 20 of the parking brake control device 19 will be described with reference to FIG. Note that the processing in FIG. 4 is repeatedly executed at predetermined time intervals (at a predetermined sampling frequency) while the parking brake control device 19 is energized.

  For example, when the processing operation of FIG. 4 is started by system activation (vehicle system activation, parking brake control device 19 activation) such as accessory ON, ignition ON, power ON, etc. by the driver's operation, the arithmetic circuit 20 1, it is determined whether or not the vehicle is stopped. This determination can be made based on the vehicle speed (vehicle speed). That is, for example, when the vehicle speed continues for a predetermined time (for example, 30 ms) due to deceleration during traveling for a predetermined time (for example, 30 ms), it is determined that the vehicle is stopped, and the vehicle speed increases from the stop to 5 km / h. When the above state continues for a predetermined time (for example, 30 ms), it can be determined that the vehicle is traveling. As the vehicle speed, for example, the speed of the wheels 2 and 3 (wheel speed) acquired from the vehicle data bus 16 can be used. In addition to the wheel speed, for example, other vehicle speed information such as a vehicle speed obtained from the rotation speed of the rotation shaft of the vehicle transmission may be used.

  If “YES” in step 1, that is, if it is determined that the vehicle is stopped, the process proceeds to step 2. In step 2, it is determined whether or not there is a parking brake holding request. In this determination, for example, when the parking brake switch 18 is operated to the braking side (parking brake ON side), it can be determined that there is a holding request. In addition to this, it is possible to determine that there is a holding request when the driver's intention to stop is detected in addition to the operation of the parking brake switch 18. For example, when the door is opened, when the seat belt is released, or when the shift lever is operated to P (parking), an automatic holding request signal based on the above-described parking brake holding determination logic is output. Sometimes it can be determined that there is a holding request. The determination that there is a holding request is a case where a new operation request signal in the present embodiment is generated.

  If “YES” in step 2, that is, it is determined that there is a holding request, the process proceeds to step 3. In step 3, it is determined whether or not the control state is such that the parking brake can be held. Specifically, it is determined whether the control state of the disc brake 31 is “holding”, “holding”, “released”, or “released”. If it is determined in step 3 that “YES”, that is, the control state of the disc brake 31 is any one of “holding”, “holding”, “released”, and “released”, step 4 is performed. The current control state is set to “holding”, that is, “holding” is stored in the storage unit 21 of the parking brake control device 19, and holding control is performed in the subsequent step 5. When the holding control is completed in step 5, the current control state is set to "holding" in step 6, that is, "holding" is stored (rewritten) in the storage unit 21 of the parking brake control device 19, and the return is returned. Return to the start, and repeat the process from step 1 onwards.

  Here, when the control state is “hold” in step 3, holding control is performed in step 5, whereby the electric actuator 43 is further driven to the holding side from the holding position at that time. Thereby, the braking force (stopping force) by the parking brake can be increased (thrust is increased). When the control state is “holding” in step 3, holding control is performed in step 5, whereby the electric actuator 43 is driven from the position in the middle of holding to the holding side. As a result, the holding control is resumed from an incomplete holding control intermediate state. When the control state is “released” in step 3, holding control is performed in step 5, whereby the electric actuator 43 is driven from the release position to the holding side. Thereby, the braking force by a parking brake is provided. When the control state is “released” in step 3, holding control is performed in step 5, whereby the electric actuator 43 is driven to the holding side from a position in the middle of release. Accordingly, the holding control is performed (resumed) from the midway state of the release control that is not completed.

  If it is determined in step 3 that the control state of the disc brake 31 is “unknown”, the process proceeds to return without passing through steps 4, 5, and 6. The process after step 1 is repeated. That is, when the control state is “unknown”, the holding control is not performed even if there is a holding request.

  On the other hand, if it is determined as “NO” in step 2, that is, it is determined that there is no holding request, the process proceeds to step 7. In step 7, it is determined whether or not there is a parking brake release request. For example, this determination can be made when there is a release request when the parking brake switch 18 is operated to the release side (parking brake OFF side). In addition to this, in addition to the operation of the parking brake switch 18, it can be determined that there is a release request when the driver's intention to start is detected. For example, when the accelerator pedal is operated, when the clutch pedal is operated, or when the shift lever is operated in a position other than P or N (neutral), the automatic release based on the above-described determination logic for releasing the parking brake. When the request signal is output, it can be determined that there is a release request. The determination that there is a release request is when a new operation request signal in the present embodiment is generated.

  If “YES” in step 7, that is, if it is determined that there is a release request, the process proceeds to step 8. In step 8, it is determined whether or not the control state is such that the parking brake can be released. Specifically, it is determined whether the control state of the disc brake 31 is “holding”, “holding”, or “released”. If it is determined in step 8 that “YES”, that is, the control state of the disc brake 31 is any one of “holding”, “holding”, and “released”, the process proceeds to step 9 and the current state The control state is set to “released”, that is, “released” is stored in the storage unit 21 of the parking brake control device 19, and release control is performed in subsequent step 10. When the release control is completed in step 10, the current control state is set to "release" in step 11, that is, "release" is stored (rewritten) in the storage unit 21 of the parking brake control device 19, and the return is returned. Return to the start, and repeat the process from step 1 onwards.

  Here, when the control state is “hold” in step 8, release control is performed in step 10, whereby the electric actuator 43 is driven from the hold position to the release side. Thereby, the parking brake is released. When the control state is “holding” in step 8, release control is performed in step 10, whereby the electric actuator 43 is driven to the release side from a position in the middle of holding. Thereby, the release control is performed (resumed) from the midway state of the incomplete holding control. When the control state is “being released” in step 8, release control is performed in step 10, whereby the electric actuator 43 is driven from the position in the middle of release to the release side. As a result, the release control is resumed from the incomplete state of the release control.

  If it is determined in step 8 that “NO”, that is, the control state of the disc brake 31 is “released” or “unknown”, the process proceeds to return without going through steps 9, 10, and 11. The process after step 1 is repeated through the start. That is, when the control state is “release” or “unknown”, release control is not performed even if a release request is made. In this case, when the control state is “release”, it is less necessary to further drive the electric actuator 43 to the release side even if a release request is made. If “NO” in step 7, that is, if it is determined that there is no release request, the process proceeds to return without going through steps 8, 9, 10, and 11, and the processes in and after step 1 are repeated through the start.

  On the other hand, if it is determined “NO” in step 1, that is, if the vehicle is running, the process proceeds to step 12. In step 12, it is determined whether or not there is a parking brake holding request (emergency stop request). For example, this determination may be made when there is a holding request (emergency stop request) when the driver operates the parking brake switch 18 on the braking side (parking brake ON side) for a predetermined time (for example, 1 second). it can.

  If “YES” in step 12, that is, if it is determined that there is a holding request (emergency stop request), the process proceeds to step 13. In step 13, it is determined whether or not the control state is such that the parking brake can be held (emergency stop control). Specifically, it is determined whether or not the control state of the disc brake 31 is “released”. If “YES” in step 13, that is, if the control state of the disc brake 31 is determined to be “released”, the process proceeds to step 14, and parking brake holding control, that is, the parking brake is used as an auxiliary brake. Perform emergency stop control.

  In this emergency stop control, for example, the electric actuator 43 is driven to the holding side so that a braking force lower than a braking force applied as a parking brake (braking force for maintaining the stop) is generated while the vehicle is stopped. . In this case, for example, by driving the electric actuator 43 based on the wheel speed information detected by the control unit 13 of the ESC 11, it is possible to perform ABS control that suppresses slipping of the wheels 2 and 3. Specifically, when the electric actuator 43 is driven to the holding side when the wheel (rear wheel 3) is not locked, braking is held, and the wheel (rear wheel 3) is locked (rear wheel 3). Alternatively, the braking may be intermittently released by driving to the release side. Thereby, the running vehicle can be stopped stably. When the holding control (emergency stop control) is completed at step 14, the process returns to the start via return, and the processes after step 1 are repeated. In this case, in the holding control (emergency stop control), since the braking force lower than the braking force applied as the parking brake is generated, the control state remains “released” (the control state is not rewritten to “activate”). .

  If it is determined in step 13 that “NO”, that is, the control state of the disc brake 31 is one of “holding”, “holding”, “released”, or “unknown”, step The process proceeds to RETURN without going through 14, and the processes after step 1 are repeated through START. That is, when the control state is “holding”, “holding”, “released”, or “unknown”, the holding control (emergency stop control) is not performed even if a holding request is made. In this case, for example, when the control state is “holding”, “released”, or “unknown”, the left and right disc brakes 31 may have different magnitudes of braking force. This is because it is considered unpreferable to apply a braking force by the parking brake as an auxiliary brake from that state (perform emergency stop control). In this case, the driver who wants to hold the parking brake (emergency stop) operates the parking brake switch 18 to the release side once to release the parking brake (completely release), and then the parking brake switch. By operating 18 to the braking side, an emergency stop using the parking brake as an auxiliary brake can be performed.

  On the other hand, if it is determined in step 12 that “NO”, that is, there is no holding request (emergency stop request), the process proceeds to step 15. Since the processing from step 15 to step 19 is the same as the processing from step 7 to step 11, the description thereof is omitted.

  FIG. 5 shows the transition of the controlled state according to the first embodiment.

  Here, “(1) Normal control state” indicates a case where the holding control and the release control are normally completed. The control state at the start time is “release”, and the electric actuator 43 is stopped. When a holding request is generated at the time point (a), the electric actuator 43 is driven to the holding side, and the control state is switched to “holding” (the storage in the storage unit 21 is rewritten to “holding”). When the holding control is completed at the time point (b), the electric actuator 43 stops and the control state is switched to “holding” (the storage in the storage unit 21 is rewritten to “holding”). When a release request is generated at the time point (c), the electric actuator 43 is driven to the release side, and the control state is switched to “released” (the storage in the storage unit 21 is rewritten to “released”). When the release control is completed at the time point (d), the electric actuator 43 stops and the control state is switched to “release” (the storage in the storage unit 21 is rewritten to “release”).

  On the other hand, “(2) Control state when holding control is interrupted” indicates a case where holding control is interrupted. The control state at the start time is “release”, and the electric actuator 43 is stopped. When a holding request is generated at the time point (a), the electric actuator 43 is driven to the holding side, and the control state is switched to “holding”. When the system is turned off (system down) at the time point (b), the electric actuator 43 stops. When the system is turned on (returned to the system) at the time point (c), the stored control state is “holding” (detected), but no new operation request signal has been generated. The actuator 43 is not driven. When a release request (new operation request signal) is generated at the time point (d), the electric actuator 43 starts driving to the release side, and the control state is switched to “being released”. When the release control is completed at the time point (e), the electric actuator 43 stops and the control state is switched to “release”.

  Furthermore, “(3) Control state when canceling control is interrupted” indicates a case where canceling control is interrupted. The control state at the start time is “hold”, and the electric actuator 43 is stopped. When a release request is generated at the point (a), the electric actuator 43 is driven to the release side, and the control state is switched to “being released”. When the system is turned off (system down) at the time point (b), the electric actuator 43 stops. When the system is turned on (recovered from the system) at the time point (c), the stored control state is “released” (detected), but no new operation request signal has been generated. The actuator 43 is not driven. When a holding request (new operation request signal) is generated at the time point (d), the electric actuator 43 starts driving to the holding side, and the control state is switched to “holding”. When the holding control is completed at the time point (e), the electric actuator 43 is stopped and the control state is switched to “holding”.

  In the first embodiment, even if the system is turned off during the control (operation or holding) of the parking brake, when the system is subsequently restored, control according to the driver's intention can be performed.

  That is, in the first embodiment, the parking brake control device 19 is on condition that a new operation request signal is generated by the processing of steps 2, 3, 7, 8, 12, 15, and 16. Resume incomplete control halfway. Thereby, the parking brake control apparatus 19 can restart incomplete control based on the new operation request signal along the driver's intention to stop and travel. For this reason, when the system returns, control according to the driver's intention can be performed.

  In the first embodiment, the parking brake control device 19 is the same as the operation request signal of the control in which a new operation request signal is not completed by the processing of step 3, step 8, and step 16 (matches). ) And the case where the new operation request signal is different from the operation request signal of the control that has not been completed, the control according to the new operation request signal is resumed. For this reason, the control according to the new operation request signal can be resumed based on the new operation request signal according to the driver's intention to stop and travel.

  In the first embodiment, when the parking brake control device 19 determines in step 1 that the vehicle is running, the parking brake control device 19 has suspended the holding or releasing control in an incomplete state by the processing in step 13. Even if this is detected, if the new operation request signal is an operation request signal for holding the disc brake 31, it is prohibited to resume incomplete control halfway. For this reason, when the vehicle is traveling, the emergency stop using the parking brake as an auxiliary brake can be stably performed.

  Next, FIG. 6 and FIG. 7 show a second embodiment. The feature of the second embodiment is that when the new operation request signal is the same as (matches) the operation request signal of the control that has not been completed, the control according to the new operation request signal is resumed. When the new operation request signal is different from the operation request signal for the control that has not been completed, it is configured to prohibit the restart of the control according to the new operation request signal. In other words, the control is resumed only when the new operation request signal coincides with the operation request signal of the incomplete control. In the second embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  The processing of step 21 and step 22 in FIG. 6 is the same as the processing of step 1 and step 2 of FIG. 4 of the first embodiment described above. Step 23 is a process used in the second embodiment instead of step 3 in the first embodiment. In step 23, it is determined whether the control state of the disc brake 31 is “holding”, “holding”, or “released”. If it is determined in step 23 that “YES”, that is, the control state of the disc brake 31 is any one of “holding”, “holding”, and “released”, the process proceeds to step 24. The processing from step 24 to step 26 is the same as the processing from step 4 to step 6 in FIG. 4 of the first embodiment described above.

  On the other hand, if it is determined in step 23 that “NO”, that is, the control state of the disc brake 31 is “unknown” or “released”, the process proceeds to return without going through steps 24, 25, and 26. Then, the processes after step 1 are repeated through the start. In other words, when the control state is “unknown” or “released”, the holding control is not performed even if there is a holding request. Accordingly, when the new operation request signal (holding request) is different from the operation request signal (release request) of the control that has not been completed, it is prohibited to resume the control according to the new operation request signal. It is configured.

  The processing of steps 27, 29, 30, and 31 is the same as the processing of steps 7, 9, 10, and 11 of FIG. 4 of the first embodiment described above. Step 28 is a process used in the second embodiment instead of step 8 in the first embodiment. In this step 28, it is determined whether or not the control state of the disc brake 31 is “holding” or “releasing”. If it is determined in step 28 that “YES”, that is, the control state of the disc brake 31 is “holding” or “released”, the process proceeds to step 29.

  On the other hand, if it is determined in step 28 that “NO”, that is, the control state of the disc brake 31 is “unknown”, “holding”, or “released”, the process goes through steps 29, 30, and 31. Return to the return, and repeat the process from step 1 through the start. That is, when the control state is “unknown”, “holding”, or “released”, the release control is not performed even if a release request is made. As a result, when the new operation request signal (release request) is different from the operation request signal (holding request) of the control that has not been completed, it is prohibited to resume the control according to the new operation request signal. It is configured.

  The processing from step 32 to step 34 is the same as the processing from step 12 to step 14 in FIG. 4 of the first embodiment described above. The processing from step 35 to step 39 is the same as the processing from step 27 to step 31.

  FIG. 7 shows the transition of the controlled state according to the second embodiment.

  Here, “(1) normal state control state” is the same as that in the first embodiment (“(1) normal state control state” in FIG. 5), and thus the description thereof is omitted.

  On the other hand, “(2) Control state when holding control is interrupted” indicates a case where holding control is interrupted. The control state at the start time is “release”, and the electric actuator 43 is stopped. When a holding request is generated at the time point (a), the electric actuator 43 is driven to the holding side, and the control state is switched to “holding”. When the system is turned off (system down) at the time point (b), the electric actuator 43 stops.

  When the system is turned on (returned to the system) at the time point (c), the stored control state is “holding” (detected), but no new operation request signal has been generated. The actuator 43 is not driven. Even if a release request (new operation request signal) is generated at the time point (d), the electric actuator 43 does not start driving to the release side. That is, the release request at the time (d) is different from the holding request at the time (a). When a holding request (new operation request signal) is generated at the time (e), the electric actuator 43 starts driving to the holding side. This is because the holding request at the time (e) matches the holding request at the time (a). When the holding control is completed at the time of (f), the electric actuator 43 is stopped and the control state is switched to “holding”.

  Furthermore, “(3) Control state when canceling control is interrupted” indicates a case where canceling control is interrupted. The control state at the start time is “hold”, and the electric actuator 43 is stopped. When a release request is generated at the point (a), the electric actuator 43 is driven to the release side, and the control state is switched to “being released”. When the system is turned off (system down) at the time point (b), the electric actuator 43 stops.

  When the system is turned on (recovered from the system) at the time point (c), the stored control state is “released” (detected), but no new operation request signal has been generated. The actuator 43 is not driven. Even if a holding request (new operation request signal) is generated at the time of (d), the electric actuator 43 does not start driving to the holding side. That is, the hold request at the time (d) is different from the release request at the time (a). When a release request (new operation request signal) is generated at the time (e), the electric actuator 43 starts driving to the release side. In this case, the release request at the time point (e) matches the release request at the time point (a). When the release control is completed at the time (f), the electric actuator 43 stops and the control state is switched to “release”.

  In the second embodiment, whether or not the holding control or the release control is performed is determined by steps 23, 28, and 36 as described above. The basic operation of the second embodiment is described above. There is no special difference.

  In particular, according to the second embodiment, the parking brake control device 19 is the same as the operation request signal of the control in which a new operation request signal is incomplete due to the processing of step 23, step 28, and step 36. In some cases, the control according to the new operation request signal is resumed, and when the new operation request signal is different from the operation request signal of the control that has not been completed, the control according to the new operation request signal is performed. It is configured to prohibit restarting. That is, resumption of control is prohibited when the operation request signal for incomplete control is different from the new operation request signal. For this reason, it is possible to perform control more in line with the driver's intention.

  In the first embodiment and the second embodiment described above, the processing program (control logic) stored in the memory of the parking brake control device 19 is selected (set) at the stage of manufacturing, shipping, or the like, for example. ), It is possible to easily cope with any form. In this case, any processing program (control logic) can be used for configurations with mechanical limitations of the system, for example, configurations in which the next operation cannot be started until the holding or release is completely completed. It is possible to respond flexibly by selecting (setting).

  In each of the above-described embodiments, the case where the left and right rear wheel side brakes are the disc brakes 31 with the electric parking brake function has been described as an example. However, the present invention is not limited to this. For example, the brakes of all the wheels (all four wheels) may be constituted by disc brakes with an electric parking brake function.

  In the above-described embodiment, the hydraulic disc brake 31 with the electric parking brake has been described as an example. However, the present invention is not limited to this. For example, an electric disc brake that does not require supply of hydraulic pressure may be used. Further, the present invention is not limited to the disc brake type brake mechanism, and may be configured as a drum brake type brake mechanism, for example. Furthermore, for example, the brake mechanism may be configured by a drum-in disc brake in which a drum-type electric parking brake is provided on the disc brake.

  According to the above embodiment, even if the system is turned off during the control (holding or releasing) of the brake mechanism, the control according to the driver's intention can be performed when the system is subsequently restored. .

  That is, the actuator control means restarts the incomplete control from the middle on condition that a new operation request signal is generated. Thereby, the actuator control means can restart the incomplete control based on the new operation request signal in accordance with the driver's intention to stop and travel. For this reason, when the system returns, control according to the driver's intention can be performed.

  According to the embodiment, the actuator control means is operable when the new operation request signal is the same as the operation request signal for the incomplete control and when the new operation request signal is incomplete. When it is different from the request signal, the control according to the new operation request signal is resumed. In this case, based on a new operation request signal in accordance with the driver's intention to stop and travel, control according to the new operation request signal can be resumed.

  According to the embodiment, when the new operation request signal is the same as the operation request signal of the control that has not been completed, the actuator control means restarts the control according to the new operation request signal, and When the operation request signal is different from the operation request signal for the control that has not been completed, it is prohibited to resume the control according to the new operation request signal. In this case, since the resumption of control is prohibited when the operation request signal for incomplete control differs from the new operation request signal, it is possible to perform control more in line with the driver's intention.

  According to the embodiment, when the vehicle is running, the actuator control unit detects that the holding or releasing control has been interrupted without being completed, and a new operation request signal is output from the brake mechanism. In the case of the holding operation request signal, it is prohibited to resume the incomplete control from the middle. In this case, the emergency stop using the parking brake as the auxiliary brake can be stably performed when the vehicle is traveling.

14 Battery (Power)
19 Parking brake control device (actuator control means)
31 Disc brake (brake mechanism)
43 Electric actuator

Claims (4)

An electric actuator that operates the brake mechanism in response to an operation request signal;
Actuator control means for controlling the holding and release of the brake mechanism by controlling the operation of the electric actuator by a power source provided in the vehicle;
With
When it is detected that the actuator control means returns to the system after the system is turned off during the holding or releasing control of the brake mechanism, and the holding or releasing control is interrupted without being completed, An electric brake device characterized by restarting the incomplete control halfway when a new operation request signal is generated.   When the actuator control means is the same as the operation request signal of the control in which the new operation request signal is incomplete, and when the new operation request signal is different from the operation request signal of the control incomplete The electric brake device according to claim 1, wherein the control according to the new operation request signal is resumed.   When the new operation request signal is the same as the operation request signal of the control that has not been completed, the actuator control means restarts the control according to the new operation request signal, and the new operation request signal is not yet received. 2. The electric brake device according to claim 1, wherein when the operation request signal is different from the completed control request signal, it is prohibited to restart the control according to the new operation request signal.   When the vehicle is running, the actuator control means detects that the holding or releasing control has been interrupted without being completed. 4. The electric brake device according to claim 1, wherein in the case of a request signal, resumption of the incomplete control from the middle is prohibited.

Images